221870831 has 16 divisors (see below), whose sum is σ = 273444864. Its totient is φ = 175306464.

The previous prime is 221870807. The next prime is 221870837. The reversal of 221870831 is 138078122.

It is a cyclic number.

It is not a de Polignac number, because 221870831 - 2⁶ = 221870767 is a prime.

It is a super-2 number, since 2×221870831² = 98453331297261122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221870837) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 97796 + ... + 100038.

It is an arithmetic number, because the mean of its divisors is an integer number (17090304).

Almost surely, 2^221870831 is an apocalyptic number.

221870831 is a deficient number, since it is larger than the sum of its proper divisors (51574033).

221870831 is a wasteful number, since it uses less digits than its factorization.

221870831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3350.

The product of its (nonzero) digits is 5376, while the sum is 32.

The square root of 221870831 is about 14895.3291672255. The cubic root of 221870831 is about 605.3874357386.

The spelling of 221870831 in words is "two hundred twenty-one million, eight hundred seventy thousand, eight hundred thirty-one".